It happened near 30th Avenue and Lincoln Way in the Outer Sunset neighborhood Thursday morning.
Video shows a man cross the street and hit a woman with some kind of weapon as she was throwing out trash.
Then the man just walks away.
The woman was not seriously injured.
Her family tells ABC7 they've lived in the neighborhood for more than a decade.
They say they're heartbroken and angry, and they hope someone will have information to help police.
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